[TenTec] Model 253 band decoder

[CSM(r) Gary Huber]

For those who may have missed it due to the Dayton Hamvention,  I submitted 
a band decoder solution for the model 253 Automatic Antenna Coupler (also 
works for the Hercules Linear Amplifier) when using the OMNI-VII or other 
TenTec transceivers lacking a band output.

See http://tentecwiki.org/doku.php?id=253banddecoder

or

I recently completed a band decoding interface for the TenTec model 253 
Automatic Antenna Coupler. The 253 requires a voltage of +10 to +14 VDC at 3 
ma on one of seven pins to select the preset tuning information for up to 
seven memories on each of four switch positions (28 memories). Originally 
the voltage and pin selection was provided by the TenTec transceiver, but
the OMNI-VII does not.

I used Commander to provide BCD via the computer parallel port to the 
(solder pads ABCD) UM BCD-10, the band is decoded (J1 1-9) which then pulls 
down pin 2 of the selected (band) 8L01 DIP Relay, which upon contact closure 
outputs +12 VDC on pin 14 to one of seven Band Select pins on the #86027-26 
to the 15 pin Molex® on the rear panel of the model 253 tuner. Pins 6 and 8 
of the 8L01 DIP Relay are at +12 VDC supplied by +VR of BCD-10. The UM 
BCD-10 receives +12 VDC from the OMNI-VII Power Supply.

references:
Model 253 Operators Manual pages v, 2-4, 2-5
8L01-DIP-Relay-PDF page 27
http://www.unifiedmicro.com/decoder.html (bcd1.jpg)
http://www.dxlabsuite.com/commander/Help/index.htm


73 es DX,

Gary - AB9M